Electric vehicle and discharging apparatus thereof

ABSTRACT

A discharging apparatus for an electric vehicle and an electric vehicle are provided. The discharging apparatus comprises: an AC charging interface; a charging connection device, having a first terminal connected with the AC charging interface and a second terminal connected with an exterior equipment, and configured to transmit an AC output from the AC charging interface to the exterior equipment; an instrument, configured to send a discharging preparation instruction; a controller, configured to detect whether the charging connection device is connected with the AC charging interface, and if yes, to switch to an external discharging mode; a battery manager, configured to control an external discharging circuit in a high-voltage distribution box of the electric vehicle to be connected after the controller switches to the external discharging mode; a power battery, connected with the high-voltage distribution box and configured to provide a DC via the external discharging circuit.

CROSS-REFERENCE TO RELATED APPLICATION

This U.S. application claims priority under 35 U.S.C. 371 to, and is aU.S. National Phase application of, the International Patent ApplicationNo. PCT/CN2012/088098, filed Dec. 31, 2012, which claims the benefit ofprior Chinese Application No. 201110458395.6 filed Dec. 31, 2011, No.201120571932.3 filed Dec. 31, 2011, No. 201210185660.2 filed Jun. 7,2012, No. 201220266009.3 filed Jun. 7, 2012, No. 201220303636.X filedJun. 27, 2012, and No. 201210214502.5 filed Jun. 27, 2012. The entirecontents of the above-mentioned patent applications are incorporated byreference as part of the disclosure of this U.S. application.

FIELD

The present disclosure relates to a vehicle control technology field,and more particularly to an electric vehicle and a discharging apparatusthereof.

BACKGROUND

With the development of science and technology, fuel vehicles are beingreplaced by environment friendly and energy saving electric vehicles.However, the popularization of the electric vehicles encounters someproblems, among which high driving mileage and fast charging technologyhas become major problems in the promotion of electric vehicles.

Currently, large-capacity batteries are used in most electric vehicles.However, although these batteries may enhance the endurance time of theelectric vehicle, they make a charging time too long. Although aspecialized DC (direct current) charging station may charge a batteryquickly, problems such as high cost and large occupied area make thepopularity of such an infrastructure encounter a certain difficulty.Moreover, because of a limited space of an electric vehicle, anin-vehicle charger may not satisfy the requirement of a charging powerdue to the limitation of its volume.

A charging solution currently used in the market comprises the followingsolutions.

Solution (1)

As shown in FIGS. 1-2, an in-vehicle charging or discharging device inthis solution mainly includes a three-phase power transformer 1′, athree-phase bridge circuit 2′ consisting of six thyristor elements, aconstant-voltage control device AUR, and a constant-current controldevice ACR. However, this solution causes a serious waste of space andcost.

Solution (2)

As shown in FIG. 3, an in-vehicle charging or discharging device in thissolution includes two charging sockets 15′, 16′ to adapt to thesingle-phase/three-phase charging, which increases the cost. A motordriving loop includes a filtering module consisting of an inductor L1′and a capacitor C1′. When a motor is driven, a loss of a three-phasecurrent is generated when it flows through the filtering module, whichcauses a waste of an electric quantity of a battery. With this solution,during the charging or discharging operation, an inverter 13′rectifies/inverts an AC (alternating current) electricity, and thevoltage after the rectifying/inverting may not be adjusted, such that anoperation voltage range of the battery is narrow.

Therefore, most AC charging technologies currently used in the marketare a single-phase charging technology, which has disadvantagesincluding low charging power, long charging time, large hardware volume,single function, restriction by voltage levels of different regionalgrids, etc.

In addition, the electric vehicle only supplies the electric energystored in the power battery to the motor so that the motor driveelectric vehicles to move. While the electric vehicle is in OK gear,after the electric vehicle collects the gear signal and the throttlesignal, the motor driving controller inverts DC supplied by the batteryinto AC and outputs the AC to the motor. Then the motor rotates to drivethe electric vehicle. The power battery with large capacity and goodquality is mounted in the electric vehicle as an energy storage device.The power battery is merely used as a power supply device, which limitsuses of the energy stored in the power battery.

With the development of science and technology, people's life has becomemore and more comfortable, and developments of various fields more andmore touch life. The electric vehicle only supplies the electric energystored in the power battery to the motor so that the motor driveelectric vehicles to move. While the electric vehicle is in OK gear,after the electric vehicle collects the gear signal and the throttlesignal, the motor driving controller inverts DC supplied by the batteryinto AC and outputs the AC to the motor. Then the motor rotates to drivethe electric vehicle.

SUMMARY

Embodiments of the present disclosure seek to solve at least one of theproblems existing in the related art to at least some extent.

Accordingly, a first object of the present disclosure is to provide adischarging apparatus for an electric vehicle. The electric vehiclebroadens an application range of electric vehicles, such that theelectric vehicle may provide a convenient household power supply forpeople at any time. A second object of the present disclosure is toprovide an electric vehicle.

In order to achieve the above objects, embodiments of a first aspect ofthe present disclosure provide a discharging apparatus for an electricvehicle. The discharging apparatus for an electric vehicle includes: anAC charging interface; a charging connection device, having a firstterminal connected with the AC charging interface and a second terminalconnected with an exterior equipment, and configured to transmit an ACoutput from the AC charging interface to the exterior equipment; aninstrument, configured to send a discharging preparation instructionafter receiving a trigger signal; a controller, configured tocommunicate with the instrument and to detect whether the chargingconnection device is connected with the AC charging interface afterreceiving the discharging preparation instruction, and if yes, to switchto an external discharging mode; a battery manager, configured tocommunicate with the controller and to control an external dischargingcircuit in a high-voltage distribution box of the electric vehicle to beconnected after the controller switches to the external dischargingmode; a power battery, connected with the high-voltage distribution boxand configured to provide a DC via the external discharging circuit inthe high-voltage distribution box; wherein the controller is configuredto convert the DC provided by the external discharging circuit into theAC and to output the AC to the AC charging interface so as to dischargeto the exterior equipment.

With the discharging apparatus for the electric vehicle according toembodiments of the present disclosure, when the electric vehicle is setin a mode of discharging to a household appliance and in OK gear, and avehicle-to-MPS (multi-plug socket) discharging connection device (i.e.,the charging connection device) is connected to the electric vehicle,after the electric vehicle detects a normal connection without fault,the electric vehicle may output a household electricity of the samevoltage grade and the same frequency as a power grid via the AC charginginterface of the electric vehicle. The electric vehicle can be normallyused for supplying electric energy as long as the household appliance isconnected with the multi-plug socket. The discharging apparatus for theelectric vehicle broadens the application range of electric vehicles,such that the electric vehicle may provide a convenient household powersupply for people at any time.

Embodiments of a second aspect of the present disclosure provide anelectric vehicle. The electric vehicle includes the dischargingapparatus for an electric vehicle according to the first aspect of thepresent disclosure.

With the electric vehicle according to embodiments of the presentdisclosure, when the electric vehicle is set in a mode of discharging toa household appliance and in OK gear, and the vehicle-to-MPS dischargingconnection device is connected to the electric vehicle, after theelectric vehicle detects a normal connection without fault, the electricvehicle may output a household electricity of the same voltage grade andthe same frequency as a power grid via the AC charging interface of theelectric vehicle. The electric vehicle can be normally used forsupplying electric energy as long as the household appliance isconnected with the multi-plug socket. The electric vehicle broadens theapplication range of electric vehicles, such that the electric vehiclemay provide a convenient household power supply for people at any time.

Additional aspects and advantages of embodiments of present disclosurewill be given in part in the following descriptions, become apparent inpart from the following descriptions, or be learned from the practice ofthe embodiments of the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other aspects and advantages of embodiments of the presentdisclosure will become apparent and more readily appreciated from thefollowing descriptions made with reference to the drawings, in which:

FIG. 1 is a circuit diagram of a conventional in-vehiclecharging-discharging device;

FIG. 2 is a diagram of a conventional in-vehicle charging-dischargingdevice;

FIG. 3 is a circuit diagram of another conventional in-vehiclecharging-discharging device;

FIG. 4 is a block diagram of a discharging apparatus for an electricvehicle according to an embodiment of the present disclosure;

FIG. 5 is a block diagram of a discharging apparatus for an electricvehicle according to another embodiment of the present disclosure;

FIG. 6 is a connecting topological diagram showing an electric vehicledischarging to a multi-plug socket;

FIG. 7 is a block diagram of a power system for an electric vehicle;

FIG. 8 is a topological diagram of a power system for an electricvehicle;

FIG. 9 is a schematic view of electric vehicles showing V-to-HI (anelectric vehicle discharging to a household appliance or an industrialappliance);

FIG. 10 is a schematic view of connecting apparatus showingvehicle-to-MPS discharging;

FIG. 11 is a system block diagram for a solution of V-to-HI;

FIG. 12 is a flow chart illustrating operations of modules during aV-to-HI discharging preparation period; and

FIG. 13 is a flow chart illustrating operations of modules during aV-to-HI discharging period and a V-to-HI discharging finish period.

DETAILED DESCRIPTION

Reference will be made in detail to embodiments of the presentdisclosure. The same or similar elements and the elements having same orsimilar functions are denoted by like reference numerals throughout thedescriptions. The embodiments described herein with reference todrawings are explanatory, illustrative, and used to generally understandthe present disclosure. The embodiments shall not be construed to limitthe present disclosure.

In the specification, it should be understood that, the terms such as“central”, “longitudinal”, “lateral”, “width”, “thickness”, “above”,“below”, “front”, “rear”, “right”, “left”, “vertical”, “horizontal”,“top”, “bottom”, “inner”, “outer”, “clockwise”, “counter-clockwise”should be construed to refer to the orientation as then described or asshown in the drawings. These terms are merely for convenience andconcision of description and do not alone indicate or imply that thedevice or element referred to must have a particular orientation. Thus,it cannot be understood to limit the present disclosure.

In addition, terms such as “first” and “second” are used herein forpurposes of description and are not intended to indicate or implyrelative importance or significance or impliedly indicate quantity ofthe technical feature referred to. Thus, the feature defined with“first” and “second” may comprise one or more this feature. In thedescription of the present disclosure, “a plurality of” means two ormore than two, unless specified otherwise.

In the present invention, unless specified or limited otherwise, theterms “mounted,” “connected,” “coupled,” “fixed” and the like are usedbroadly, and may be, for example, fixed connections, detachableconnections, or integral connections; may also be mechanical orelectrical connections; may also be direct connections or indirectconnections via intervening structures; may also be inner communicationsof two elements, which can be understood by those skilled in the artaccording to specific situations.

In the present invention, unless specified or limited otherwise, astructure in which a first feature is “on” or “below” a second featuremay include an embodiment in which the first feature is in directcontact with the second feature, and may also include an embodiment inwhich the first feature and the second feature are not in direct contactwith each other, but are contacted via an additional feature formedtherebetween. Furthermore, a first feature “on,” “above,” or “on top of”a second feature may include an embodiment in which the first feature isright or obliquely “on,” “above,” or “on top of” the second feature, orjust means that the first feature is at a height higher than that of thesecond feature; while a first feature “below,” “under,” or “on bottomof” a second feature may include an embodiment in which the firstfeature is right or obliquely “below,” “under,” or “on bottom of” thesecond feature, or just means that the first feature is at a heightlower than that of the second feature.

FIG. 4 is a block diagram of a discharging apparatus for an electricvehicle according to an embodiment of the present disclosure.

As shown in FIG. 4, a discharging apparatus 100 for an electric vehicleaccording to an embodiment of the present disclosure includes: an ACcharging interface 110, a charging connection device 120, an instrument130, a controller 140, a battery manager 150 and a power battery 160.

The charging connection device 120 has a first terminal connected withthe AC charging interface 110 and a second terminal connected with anexterior equipment, and is configured to transmit an AC output from theAC charging interface 110 to the exterior equipment.

Specifically, as shown in FIG. 5, the discharging apparatus 100 for theelectric vehicle according to another embodiment of the presentdisclosure is shown. The charging connection device 120 further includesa charging gun 1201 and a multi-plug socket 1202.

The charging gun 1201 is located at a first terminal of the chargingconnection device and is connected with the AC charging interface 110.

The multi-plug socket 1202 is located at the second terminal of thecharging connection device and is connected with a plug of the exteriorequipment.

The controller 140 is configured to communicate with the instrument 130and to detect whether the charging connection device 120 is connectedwith the AC charging interface 110 after receiving a dischargingpreparation instruction sent from the instrument 130 when the instrument130 receives a trigger signal. If the charging connection device 120 isconnected with the AC charging interface 110, the controller 140switches to an external discharging mode. In some embodiments of thepresent disclosure, the external discharge mode may be a three-phasedischarge mode or a single-phase discharge mode.

Specifically, the instrument 130 and the controller 140 are communicatedvia a CAN bus of a local area network of the controller 140, and thecontroller 140 and the battery manager 150 are communicated via the CANbus.

Furthermore, the controller 140 is further configured to determinewhether the electric vehicle is currently in P gear after it isdetermined that the charging connection device 120 is connected with theAC charging interface 110, and if yes, the controller 140 switches tothe external discharging mode. The controller 140 is further configuredto detect in real-time whether an internal circuit of the controller 140has a fault and to detect in real-time whether the exterior equipmenthas a fault during discharging. The controller 140 is further configuredto stop outputting the AC (such as a single-phase AC or a three-phaseAC) if it is determined that the internal circuit of the controller hasa fault and/or the exterior equipment has a fault. The controller 140 isfurther configured to stop outputting the AC after receiving adischarging finish instruction from the instrument 130. The controller140 is further configured to detect a current discharging current inreal-time. The AC may be 220V/50 Hz. In another embodiment, thethree-phase AC may be used, and a discharging voltage of the three-phaseAC may be adjusted to meet a usage standard of the household appliance.

The battery manager 150 is configured to communicate with the controller140 and to control an external discharging circuit in a high-voltagedistribution box of the electric vehicle to be connected after thecontroller switches to the external discharging mode.

Specifically, the battery manager 150 is further configured to detect inreal-time a current electric quantity of the power battery and whetherthe power battery 160 has a fault, if it is determined that the powerbattery 160 has a fault, the battery manager 150 sends a battery faultinstruction to the controller 140, and the controller 140 stopsoutputting the AC after receiving the battery fault instruction.

The power battery 160 is connected with the high-voltage distributionbox and is configured to provide a DC by the external dischargingcircuit in the high-voltage distribution box.

The controller 140 is configured to invert DC provided by the externaldischarging circuit into AC, and the AC is output to the AC charginginterface 110 so as to discharge to the exterior equipment, i.e. tocharge the exterior equipment.

With the discharging apparatus for the electric vehicle according toembodiments of the present disclosure, when the electric vehicle is setin a mode of discharging to a household appliance and in OK gear, andthe vehicle-to-MPS discharging connection device is connected to theelectric vehicle, after the electric vehicle detects a normal connectionwithout fault, the electric vehicle may output a household electricityof the same voltage grade and the same frequency as a power grid via theAC charging interface of the electric vehicle. The electric vehicle canbe normally used to provide electric energy as long as the householdappliance is connected with the multi-plug socket. The dischargingapparatus for the electric vehicle broadens the application range ofelectric vehicles, such that the electric vehicle may provide aconvenient household power supply for people at any time.

FIG. 6 is a connecting topological diagram showing an electric vehicledischarging to a multi-plug socket.

As shown in FIG. 6, the connecting topological diagram showing anelectric vehicle discharging to a multi-plug socket includes: acontroller, a multi-plug socket and a vehicle control device.

Specifically, because the electric vehicle is only used as a powersupply when it supplies power externally and there is no CP signal(i.e., a control confirmation signal) providing interaction between theexterior equipment and the electric vehicle, the CP signal line is notrequired to be included in the vehicle-to-MPS discharging connectiondevice, and only a CC signal line (i.e., a connecting confirmationsignal line, also referring to a PP signal line in Europe standard) isrequired. A resistance of the CC signal line is set as 470Ω todistinguish from a charging state, such that the controller may confirmthat the electric vehicle in the mode of discharging to the householdappliance.

Furthermore, when the electric vehicle is in OK gear and set in the modeof discharging to the household appliance, and the vehicle-to-MPSdischarging connection device is connected to the electric vehicle,after the electric vehicle detects a normal connection without fault,the electric vehicle outputs a household electricity of the same voltagegrade and the same frequency as a power grid via the AC charginginterface of the electric vehicle. The electric vehicle can be normallyused as a power supply as long as the household appliance is connectedwith the multi-plug socket.

FIG. 7 is a block diagram of a power system for an electric vehicle.

The power system for the electric vehicle according to an embodiment ofthe present disclosure includes a power battery 10, acharging-discharging socket 20, a bidirectional DC-DC module 30, adriving control switch 40, a bidirectional DC-AC module 50, a motorcontrol switch 60, a charging-discharging control module 70 and acontroller module 80. In some embodiments of the present disclosure, theexternal discharging circuit in the high-voltage distribution box refersto the charging-discharging control module 70, the bidirectional DC-DCmodule 30 and the bidirectional DC-AC module 50. When the power systemis controlled to be at an external discharging state, the externaldischarging circuit may externally discharge.

The bidirectional DC-DC module 30 has a first DC terminal a1 connectedwith a first terminal of the power battery 10, and a second DC terminala2 connected with a second terminal of the power battery 10. The firstDC terminal a1 is a common DC terminal for an input to and an outputfrom the bidirectional DC-DC module 30. The driving control switch 40has a first terminal connected with the second terminal of the powerbattery 10, and a second terminal connected with a third DC terminal a3of the bidirectional DC-DC module 30. The bidirectional DC-AC module 50has a first DC terminal b1 connected with the second terminal of thedriving control switch 40, and a second DC terminal b2 connected withthe first terminal of the power battery 10. The motor control switch 60has a first terminal connected with an AC terminal c of thebidirectional DC-AC module 50, and a second terminal connected with amotor M. The charging-discharging control module 70 has a first terminalconnected with the AC terminal c of the bidirectional DC-AC module 50,and a second terminal connected with the charging-discharging socket 20.The controller module 80 is connected with the driving control switch40, the motor control switch 60 and the charging-discharging controlmodule 70 respectively, and configured to control the driving controlswitch 40, the motor control switch 60 and the charging-dischargingcontrol module 70 according to a current operation mode of the powersystem.

Further, in some embodiments, the current operation mode of the powersystem may include a driving mode and a charge-discharge mode. When thecurrent operation mode of the power system is the driving mode, thecontroller module 80 controls the driving control switch 40 to turn onin order to stop the bidirectional DC-DC module 30, controls the motorcontrol switch 60 to turn on to drive the motor M normally, and controlsthe charging-discharging control module 70 to turn off. When the currentoperation mode of the power system is the charge-discharge mode, thecontroller module 80 controls the driving control switch 40 to turn offto start the bidirectional DC-DC module 30, controls the motor controlswitch 60 to turn off to remove the motor M, and controls thecharging-discharging control module 70 to turn on in such a way that anexternal power source may charge the power battery 10 normally. Thefirst DC terminal a1 and the third DC terminal a3 of the bidirectionalDC-DC module 30 are connected with a positive terminal and a negativeterminal of a DC bus respectively.

FIG. 8 is a topological diagram of a power system for an electricvehicle.

As shown in FIG. 8, the power system for the electric vehicle furtherincludes a first pre-charging control module 101. The first pre-chargingcontrol module 101 has a first terminal connected with the secondterminal of the power battery 10, and a second terminal connected withthe second DC terminal a2 of the bidirectional DC-DC module 30, and isconfigured to pre-charge a capacitor C1 in the bidirectional DC-DCmodule 30 and a bus capacitor C0 connected between the first DC terminala1 and the third DC terminal a3 of the bidirectional DC-DC module 30.The first pre-charging control module 101 includes a first switch K1, afirst resistor R1 and a second switch K2. The first switch K1 has afirst terminal connected with the second DC terminal a2 of thebidirectional DC-DC module 30. The first resistor R1 has a firstterminal connected with a second terminal of the first switch K1, and asecond terminal connected with the second terminal of the power battery10. The second switch K2 is connected in parallel with a circuitconsisting of the first resistor R1 and the first switch K1 which areconnected in series. When the power system is powered on, the controllermodule 80 controls the first switch K1 to turn on to pre-charge thecapacitor C1 in the bidirectional DC-DC module 30 and the bus capacitorC0; and when a voltage across the bus capacitor C0 is a predeterminedmultiple of a voltage of the power battery 10, the controller module 80controls the first switch K1 to turn off and controls the second switchK2 to turn on.

As shown in FIG. 8, the bidirectional DC-DC module 30 further includes afirst switching transistor Q1, a second switching transistor Q2, a firstdiode D1, a second diode D2, a first inductor L1 and a first capacitorC1. The first switching transistor Q1 and the second switchingtransistor Q2 are connected in series to form a circuit, and saidcircuit is connected between the first DC terminal a1 and the third DCterminal a3 of the bidirectional DC-DC module 30. The first switchingtransistor Q1 and the second switching transistor Q2 are controlled bythe controller module 80. A first node A is defined between the firstswitching transistor Q1 and the second switching transistor Q2. Thefirst diode D1 is connected with the first switching transistor Q1 ininverse-parallel. The second diode D2 is connected with the secondswitching transistor Q2 in inverse-parallel. The first inductor L1 has afirst terminal connected with the first node A, and a second terminalconnected with the second terminal of the power battery 10. The firstcapacitor C1 has a first terminal connected with the second terminal ofthe first inductor L1, and a second terminal connected with the firstterminal of the power battery 10.

Moreover, as shown in FIG. 8, the power system for the electric vehiclefurther includes a leakage current reducing module 102. The leakagecurrent reducing module 102 is connected between the first DC terminala1 and the third DC terminal a3 of the bidirectional DC-DC module 30.Specifically, the leakage current reducing module 102 includes a secondcapacitor C2 and a third capacitor C3. The second capacitor C2 has afirst terminal connected with a first terminal of the third capacitorC3, and a second terminal connected with the first DC terminal a1 of thebidirectional DC-DC module 30, the third capacitor C3 has a secondterminal connected with the third DC terminal a3 of the bidirectionalDC-DC module 30, and a second node B is defined between the secondcapacitor C2 and the third capacitor C3.

Generally, a leakage current is large in an inverter and grid systemwithout transformer isolation. Therefore, with the power systemaccording to embodiments of the present disclosure, the leakage currentreducing module 102 is connected between the positive terminal and thenegative terminal of the DC bus, thus reducing the leakage currenteffectively. The leakage current reducing module 102 includes twocapacitors C2 and C3 of the same type, the capacitor C2 is connectedbetween the negative terminal of the DC bus and a three-phase AC neutralpoint potential, the capacitor C3 is connected between the positiveterminal of the DC bus and the three-phase AC neutral point potential,and a high-frequency current may be fed back to a DC side when the powersystem operates, thus effectively reducing a high-frequency leakagecurrent generated when the power system operates.

In one embodiment, as shown in FIG. 8, the power system for the electricvehicle further includes a filtering module 103, a filtering controlmodule 104, an EMI-filter module 105 and a second pre-charging controlmodule 106.

The filtering module 103 is connected between the bidirectional DC-ACmodule 50 and the charging-discharging control module 70. Specifically,as shown in FIG. 5, the filtering module 103 includes inductors L_(A),L_(B), L_(C) and capacitors C4, C5, C6, and the bidirectional DC-ACmodule 50 may include six IGBTs (insulated gate bipolar transistor), aconnection point between an upper IGBT and a lower IGBT is connectedrespectively with the filtering module 103 and the motor control switch60 via a power bus.

As shown in FIG. 8, the filtering control module 104 is connectedbetween the second node B and the filtering module 103, and controlledby the controller module 80. When the current operation mode of thepower system is the driving mode, the controller module 80 controls thefiltering control module 104 to turn off. The filtering control module104 may be a capacitor switching relay, and includes a contactor K10.The EMI-filter module 105 is connected between the charging-dischargingsocket 20 and the charging-discharging control module 70. It should benoted that, the position of the contactor K10 in FIG. 8 is merelyexemplary. In other embodiments, the contactor K10 may be located atother positions, provided that the filtering module 103 may be turnedoff using the contactor K10. For example, in another embodiment, thecontactor K10 may also be connected between the bidirectional DC-ACmodule 50 and the filtering module 103.

The second pre-charging control module 106 is connected in parallel withthe charging-discharging control module 70 and configured to pre-chargecapacitors C4, C5, C6 in the filtering module 103. The secondpre-charging control module 106 includes three resistors R_(A), R_(B),R_(C) connected in series and a three-phase pre-charging switch K9.

In one embodiment, as shown in FIG. 8, the charging-discharging controlmodule 70 further includes a three-phase switch K8 and/or a single-phaseswitch K7 configured to implement a three-phase charging-discharging ora single-phase charging-discharging.

In other words, when the power system is powered on, the controllermodule 80 controls the first switch K1 to turn on to pre-charge thefirst capacitor C1 in the bidirectional DC-DC module 30 and the buscapacitor C0; and when the voltage across the bus capacitor C0 is apredetermined multiple of the voltage of the power battery 10, thecontroller module 80 controls the first switch K1 to turn off andcontrols the second switch K2 to turn on. In this way, the bidirectionalDC-DC module 30 and the large-capacity bus capacitor C0 directlyconnected between power buses (i.e. DC buses) constitute main componentsfor implementing a battery low-temperature activation technology, whichis adapted to transfer the electric energy of the power battery 10 tothe large-capacity bus capacitor C0 via the bidirectional DC-DC module30, and to transfer the electric energy stored in the large-capacity buscapacitor C0 to the power battery 10 via the bidirectional DC-DC module30 (i.e. when charging the power battery 10) after an electric quantityof the bus capacitor C0 reaches a predetermined value. Therefore, thecharging and discharging cycle of the power battery 10 makes thetemperature of the power battery 10 increase to an optimum operationtemperature range.

When the current operation mode of the power system is the driving mode,the controller module 80 controls the driving control switch 40 to turnon to stop the bidirectional DC-DC module 30, controls the motor controlswitch 60 to turn on to drive the motor M normally, and controls thecharging-discharging control module 70 to turn off. It should be notedthat, although in some embodiments, the motor control switch 60 includesthree switches connected with a three-phase input of the motor, in otherembodiments, the motor control switch 60 may also include two switchesconnected with a two-phase input of the motor, or even one switch,provided that the control on the motor may be realized. Therefore, otherembodiments will not be described in detail herein. In this way, a DCfrom the power battery 10 is inverted into an AC by means of thebidirectional DC-AC module 50, and the AC is transmitted to the motor M.The operation of the motor M can be controlled by a revolvingtransformer decoder technology and a space vector pulse width modulation(SVPWM) control algorithm.

When the current operation mode of the power system is thecharge-discharge mode, the controller module 80 controls the drivingcontrol switch 40 to turn off to start the bidirectional DC-DC module30, controls the motor control switch 60 to turn off to remove the motorM, and controls the charging-discharging control module 70 to turn on insuch a way that an external power source such as a three-phase powersource or a single-phase power source may charge the power battery 10via the charging-discharging socket 20 normally. In other words, bydetecting a charge connection signal, an AC grid electric system andrelevant information on whole vehicle battery management, a controllablerectification function may be performed be means of the bidirectionalDC-AC module 50, and the in-vehicle power battery 10 may be charged bythe single-phase power source and/or the three-phase power source viathe bidirectional DC-DC module 30.

With the power system for the electric vehicle according to embodimentsof the present disclosure, the electric vehicle can be charged under ahigh power by means of a civil or industrial AC grid, such that a usermay perform the charging efficiently, promptly, anytime and anywhere,thus saving a charging time. Moreover, a constant-voltage control deviceor a constant-current control device is not required, thus saving spaceand cost and having a wide battery operation voltage range.

FIG. 9 is a schematic view of electric vehicles showing V-to-HI.

Specifically, as shown in FIG. 9, the schematic view of electricvehicles showing V-to-HI includes electric vehicles and a vehicle-to-MPSdischarging connection device.

The vehicle-to-MPS discharging connection device is mainly used toconnect the two electric vehicles. FIG. 10 is a schematic view ofconnecting apparatus showing vehicle-to-MPS discharging. As shown inFIG. 10, the vehicle-to-MPS discharging connection device is configuredto connect the electric vehicle and the exterior household equipment. AnAC charging gun is provided at a first terminal of the vehicle-to-MPSdischarging connection device (that is, the first terminal is connectedwith the electric vehicle) and a household multi-plug socket meeting anational standard is provided at a second terminal of the vehicle-to-MPSdischarging connection device (that is, the second terminal is connectedwith a plug of the household appliance). The household multi-plug sockethas an automatic reset and an operation indicating light.

FIG. 11 is a system block diagram for a solution of V-to-HI.

Specifically, during the V-to-HI, following modules are involved intooperation: the instrument, the battery manager, the high-voltagedistribution box, the controller, the AC charging interface, and thepower battery. The instrument is configured to sample a dischargingswitch signal and a discharging mode signal, and to display discharginginformation and fault information. The battery manager is configured tosample state information of the power battery, to determine whether thepower battery is allowed to externally discharge, and to control toconnect a power supply circuit in the high-voltage distribution box. Thehigh-voltage distribution box is configured to connect the power batteryand the controller, such that the power battery may supply DC to thecontroller. The controller is configured to invert the DC supplied bythe power battery into an AC. The controller is communicated with theinstrument and the battery manager via the CAN. The AC charginginterface is configured to connect the controller and the exteriorhousehold appliance, such that the AC provided by the controller can beoutput externally. The power battery is configured to store electricenergy and to externally discharge the stored electric energy if it isrequired.

With the electric vehicle, a motor driving controller is furtherexpanded in function of inverting the DC into the AC. The improvedelectric vehicle may supply household AC. Furthermore, when the powergrid is out of service or for a place uncovered by the power grid, theelectric vehicle may be temporarily used as a charging device to supplyhousehold AC to deal with emergencies. It significantly broadens anapplication range of electric vehicles, thus easing people's life.

A process of the V-to-HI may include a preparation period, a dischargingperiod and a discharging finish period.

FIG. 12 is a flow chart showing operations of modules during the V-to-HIdischarging preparation period. FIG. 13 is a flow chart showingoperations of the modules during the V-to-HI discharging period and theV-to-HI discharging finish period.

FIG. 12 is a flow chart showing operations of modules during the V-to-HIdischarging preparation period. During the V-to-HI dischargingpreparation period, specifically, when the electric vehicle is in OKgear with P gear, the instrument starts to serve. A “discharge settinginterface” is activated by pressing an external discharge button on apanel of the instrument, and the power consumption equipment may be setas “household appliance” via an “option” key and an “OK” key on asteering wheel, in which the power consumption equipment may furtherinclude an “industrial appliance” and “electric vehicle to be charged”.After the discharging mode is set as “household appliance”, theinstrument sends a message indicating “discharging mode” to inform thecontroller and popups a prompt “please connect to dischargingequipment”. If it is determined that the electric vehicle is able toexternally discharge, a prompt is popuped, which includes a connectingstate, a current electric quantity, a discharging current and the powerconsumption equipment, for example, connected, discharging in process;the current electric quantity: 50%; the discharging current: 10 A; thepower consumption equipment: household appliance. If it is determinedthat the electric vehicle is unable to externally discharge, a prompt ispopuped indicating unconnected, please check the discharging system.

Furthermore, when the controller is in service, it is first determinedwhether there is an electric vehicle gear signal, if yes, the electricvehicle enters the driving mode; and if no, the controller detects a CCsignal to determine whether the charging gun is connected to the vehicleafter receiving the message indicating “discharging mode” from theinstrument. Specifically, the controller needs to determine whether thecharging interface CC signal is connected and whether a resistance of CCis 470Ω. If the CC signal is not detected and the resistance of CC isnot 470Ω, a message indicating “forbid external discharge” is sent tothe instrument. If the CC signal is detected and the resistance of CC is470Ω, it is further determined whether the electric vehicle is in P gearand whether the motor is in undriving mode. If the electric vehicle isnot in P gear and the motor is not in undriving mode, a messageindicating “forbid external discharge” is sent to the instrument. If theelectric vehicle is in P gear and the motor is in undriving mode, thecontroller switches the internal circuit thereof to an externaldischarge mode. A gear shifting instruction is not replied during thedischarging. The controller performs a self-detection, and if there isno fault, the controller sends a message indicating “dischargingpreparation of the controller is in ready”. It is determined whether amessage indicating “preparation of the power battery is in ready” isreceived, and if yes, the message indicating “preparation of thecontroller is in ready” is sent, an AC output switch is turned on and amessage indicating “get ready to external discharge” is sent. If themessage indicating “preparation of the power battery is in ready” is notreceived, the message indicating “forbid external discharge” is sent tothe instrument.

When it starts to work, the battery manager first self-detects whetherit is able to externally discharge, and if no, a message indicating“forbid to discharge” is sent. A condition of forbiddance of dischargeincludes any one of an over-high temperature of the power battery, anover-low temperature of the power battery, an over-low voltage of thepower battery and an over-low SOC. When receiving the message indicating“preparation of the controller is in ready”, the battery managercontrols the external discharging circuit in the high-voltagedistribution box to be connected and sends the message indicating“preparation of the power battery is in ready”.

Furthermore, after receiving the message indicating “preparation of thepower battery is in ready”, the controller connects an external outputand gets ready to work, that is, the household AC is externallysupplied, and a message indicating “start to discharge” is sent.

FIG. 13 is a flow chart showing operations of the modules during theV-to-HI discharging period and the V-to-HI discharging finish period.

During the V-to-HI discharging period and the V-to-HI discharging finishperiod, specifically, the instrument keeps displaying the dischargingstate of the electric vehicle; the controller keeps detecting whetherthere is a message indicating “the discharging is finished” from theinstrument, whether the controller has a fault, whether the exteriorequipment has a fault, and whether the power battery has a fault; andthe battery manager keeps detecting the state of the power battery andwhether the battery system has a fault.

The controller stops externally outputting the AC if any of followingcases occurs. When receiving the message indicating “the discharging isfinished” from the instrument, the controller stops externallyoutputting the AC and sends the message indicating “the discharging isfinished”, and after receiving the message indicating “the dischargingis finished”, the battery manager switches an internal circuit in thehigh-voltage distribution to reset the electric vehicle in OK gear. Whenreceiving a message indicating “a battery system fault” sent from thebattery manager, the controller stops externally outputting the AC, andthe instrument displays the fault. When receiving a message indicating“an exterior equipment fault”, the controller stops externallyoutputting the AC, and the instrument displays the fault, in which thefault of the exterior equipment includes any one of over current, shortcircuit, connection fault and a combination thereof. When it isdetermined the controller has a fault on itself, the controller stopsexternally outputting the AC and sends a message indicating “acontroller fault”, the instrument receives the message indicating “acontroller fault” and displays the fault, and the battery managerswitches to a corresponding state according to the fault.

Furthermore, during the external discharging, the controller stopsexternally outputting the AC if any of following cases occurs: SOC ofthe power battery is over-low, and a discharge control button is pressedto terminate external discharging.

With the discharging apparatus for the electric vehicle according toembodiments of the present disclosure, when the electric vehicle is inOK gear and set in the mode of discharging to the household appliance,and the vehicle-to-MPS discharging connection device (i.e., the chargingconnection device) is connected to the electric vehicle, after theelectric vehicle detects a normal connection without fault, the electricvehicle outputs a household electricity of the same voltage grade andthe same frequency as the power grid via the AC charging interface ofthe electric vehicle. The electric vehicle can be normally used foroutputting electric energy as long as the household appliance isconnected with the multi-plug socket. The discharging apparatus for theelectric vehicle broadens the application range of electric vehicles,such that the electric vehicle may provide a convenient household powersupply for people at any time.

The present disclosure further provides an electric vehicle. Theelectric vehicle includes the discharging apparatus 100 for the electricvehicle according to embodiments of the present disclosure.

When the electric vehicle according to embodiments of the presentdisclosure is set in the mode of discharging to the household applianceand in OK gear, and the vehicle-to-MPS discharging connection device isconnected to the electric vehicle, after the electric vehicle detects anormal connection without fault, the electric vehicle may output ahousehold electricity of the same voltage grade and same frequency asthe power grid via the AC charging interface of the electric vehicle.The electric vehicle can be normally used as a power source as long asthe household appliance is connected with the multi-plug socket. Theelectric vehicle broadens the application range of electric vehicles,such that the electric vehicle may provide a convenient household powersupply for people at any time.

Any procedure or method described in the flow charts or described in anyother way herein may be understood to comprise one or more modules,portions or parts for storing executable codes that realize particularlogic functions or procedures. Moreover, advantageous embodiments of thepresent disclosure comprises other implementations in which the order ofexecution is different from that which is depicted or discussed,including executing functions in a substantially simultaneous manner orin an opposite order according to the related functions. This should beunderstood by those skilled in the art to which embodiments of thepresent disclosure belong.

The logic and/or step described in other manners herein or shown in theflow chart, for example, a particular sequence table of executableinstructions for realizing the logical function, may be specificallyachieved in any computer readable medium to be used by the instructionexecution system, device or equipment (such as the system based oncomputers, the system comprising processors or other systems capable ofobtaining the instruction from the instruction execution system, deviceand equipment and executing the instruction), or to be used incombination with the instruction execution system, device and equipment.As to the specification, “the computer readable medium” may be anydevice adaptive for including, storing, communicating, propagating ortransferring programs to be used by or in combination with theinstruction execution system, device or equipment. More specificexamples of the computer readable medium comprise but are not limitedto: an electronic connection (an electronic device) with one or morewires, a portable computer enclosure (a magnetic device), a randomaccess memory (RAM), a read only memory (ROM), an erasable programmableread-only memory (EPROM or a flash memory), an optical fiber device anda portable compact disk read-only memory (CDROM). In addition, thecomputer readable medium may even be a paper or other appropriate mediumcapable of printing programs thereon, this is because, for example, thepaper or other appropriate medium may be optically scanned and thenedited, decrypted or processed with other appropriate methods whennecessary to obtain the programs in an electric manner, and then theprograms may be stored in the computer memories.

It should be understood that each part of the present disclosure may berealized by the hardware, software, firmware or their combination. Inthe above embodiments, a plurality of steps or methods may be realizedby the software or firmware stored in the memory and executed by theappropriate instruction execution system. For example, if it is realizedby the hardware, likewise in another embodiment, the steps or methodsmay be realized by one or a combination of the following techniquesknown in the art: a discrete logic circuit having a logic gate circuitfor realizing a logic function of a data signal, an application-specificintegrated circuit having an appropriate combination logic gate circuit,a programmable gate array (PGA), a field programmable gate array (FPGA),etc.

Those skilled in the art shall understand that all or parts of the stepsin the above exemplifying method of the present disclosure may beachieved by commanding the related hardware with programs. The programsmay be stored in a computer readable storage medium, and the programscomprise one or a combination of the steps in the method embodiments ofthe present disclosure when run on a computer.

In addition, each function cell of the embodiments of the presentdisclosure may be integrated in a processing module, or these cells maybe separate physical existence, or two or more cells are integrated in aprocessing module. The integrated module may be realized in a form ofhardware or in a form of software function modules. When the integratedmodule is realized in a form of software function module and is sold orused as a standalone product, the integrated module may be stored in acomputer readable storage medium.

The storage medium mentioned above may be read-only memories, magneticdisks, CD, etc.

Reference throughout this specification to “an embodiment,” “someembodiments,” “one embodiment”, “another example,” “an example,” “aspecific example,” or “some examples,” means that a particular feature,structure, material, or characteristic described in connection with theembodiment or example is included in at least one embodiment or exampleof the present disclosure. Thus, the appearances of the phrases such as“in some embodiments,” “in one embodiment”, “in an embodiment”, “inanother example,” “in an example,” “in a specific example,” or “in someexamples,” in various places throughout this specification are notnecessarily referring to the same embodiment or example of the presentdisclosure. Furthermore, the particular features, structures, materials,or characteristics may be combined in any suitable manner in one or moreembodiments or examples.

Although explanatory embodiments have been shown and described, it wouldbe appreciated by those skilled in the art that the above embodimentscannot be construed to limit the present disclosure, and changes,alternatives, and modifications can be made in the embodiments withoutdeparting from spirit, principles and scope of the present disclosure.

What is claimed is:
 1. A discharging apparatus for an electric vehicle,comprising: an AC charging interface; a charging connection device,having a first terminal connected with the AC charging interface and asecond terminal connected with an exterior equipment, and configured totransmit an AC output from the AC charging interface to the exteriorequipment; an instrument, configured to send a discharging preparationinstruction after receiving a trigger signal; a controller, configuredto communicate with the instrument and to detect whether the chargingconnection device is connected with the AC charging interface afterreceiving the discharging preparation instruction, and if yes, to switchto an external discharging mode; a battery manager, configured tocommunicate with the controller and to control an external dischargingcircuit in a high-voltage distribution box of the electric vehicle to beconnected after the controller switches to the external dischargingmode; a power battery, connected with the high-voltage distribution boxand configured to provide a DC via the external discharging circuit inthe high-voltage distribution box; wherein the controller is configuredto convert the DC provided by the external discharging circuit into theAC and to output the AC to the AC charging interface so as to dischargeto the exterior equipment; the controller is further configured todetect whether the electric vehicle is currently in P gear after it isdetermined that the charging connection device is connected with the ACcharging interface, and if yes, the controller switches to the externaldischarging mode; and the high-voltage distribution box comprises abidirectional DC-DC module and a leakage current reducing module, theleakage current reducing module is connected to the bidirectional DC-DCmodule in parallel.
 2. The discharging apparatus for an electric vehicleaccording to claim 1, wherein the instrument and the controllercommunicate via a CAN bus of a local area network of the controller, andthe controller and the battery manager communicate via the CAN bus. 3.The discharging apparatus for an electric vehicle according to claim 1,wherein the charging connection device comprises: a charging gun,located at the first terminal of the charging connection device andconnected with the AC charging interface; a multi-plug socket, locatedat the second terminal of the charging connection device and connectedwith a plug of the exterior equipment.
 4. The discharging apparatus foran electric vehicle according to claim 1, wherein the controller isfurther configured to detect in real-time whether an internal circuit ofthe controller has a fault and to detect in real-time whether theexterior equipment has a fault during discharging.
 5. The dischargingapparatus for an electric vehicle according to claim 4, wherein thecontroller is further configured to stop outputting the AC if it isdetermined that the internal circuit has a fault and/or the exteriorequipment has a fault.
 6. The discharging apparatus for an electricvehicle according to claim 1, wherein the battery manager is furtherconfigured to detect in real-time a current electric quantity of thepower battery and to detect in real-time whether the power battery has afault, if it is determined the power battery has a fault, the batterymanager sends a battery fault instruction to the controller, and thecontroller stops outputting the AC after receiving the battery faultinstruction.
 7. The discharging apparatus for an electric vehicleaccording to claim 1, wherein the controller is further configured tostop outputting the AC after receiving a discharging finish instructionfrom the instrument.
 8. The discharging apparatus for an electricvehicle according to claim 1, wherein the controller is furtherconfigured to detect a current discharging current in real-time.
 9. Anelectric vehicle, comprising a discharging apparatus for an electricvehicle, the discharging apparatus for an electric vehicle comprising:an AC charging interface; a charging connection device, having a firstterminal connected with the AC charging interface and a second terminalconnected with an exterior equipment, and configured to transmit an ACoutput from the AC charging interface to the exterior equipment; aninstrument, configured to send a discharging preparation instructionafter receiving a trigger signal; a controller, configured tocommunicate with the instrument and to detect whether the chargingconnection device is connected with the AC charging interface afterreceiving the discharging preparation instruction, and if yes, to switchto an external discharging mode; a battery manager, configured tocommunicate with the controller and to control an external dischargingcircuit in a high-voltage distribution box of the electric vehicle to beconnected after the controller switches to the external dischargingmode; a power battery, connected with the high-voltage distribution boxand configured to provide a DC via the external discharging circuit inthe high-voltage distribution box; wherein the controller is configuredto convert the DC provided by the external discharging circuit into theAC and to output the AC to the AC charging interface so as to dischargeto the exterior equipment; the controller is further configured todetect whether the electric vehicle is currently in P gear after it isdetermined that the charging connection device is connected with the ACcharging interface, and if yes, the controller switches to the externaldischarging mode; and the high-voltage distribution box comprises abidirectional DC-DC module and a leakage current reducing module, theleakage current reducing module is connected to the bidirectional DC-DCmodule in parallel.
 10. The electric vehicle according to claim 9,wherein the instrument and the controller communicate via a CAN bus of alocal area network of the controller, and the controller and the batterymanager communicate via the CAN bus.
 11. The electric vehicle accordingto claim 9, wherein the charging connection device comprises: a charginggun, located at the first terminal of the charging connection device andconnected with the AC charging interface; a multi-plug socket, locatedat the second terminal of the charging connection device and connectedwith a plug of the exterior equipment.
 12. The electric vehicleaccording to claim 9, wherein the controller is further configured todetect in real-time whether an internal circuit of the controller has afault and to detect in real-time whether the exterior equipment has afault during discharging.
 13. The electric vehicle according to claim12, wherein the controller is further configured to stop outputting theAC if it is determined that the internal circuit has a fault and/or theexterior equipment has a fault.
 14. The electric vehicle according toclaim 9, wherein the battery manager is further configured to detect inreal-time a current electric quantity of the power battery and to detectin real-time whether the power battery has a fault, if it is determinedthe power battery has a fault, the battery manager sends a battery faultinstruction to the controller, and the controller stops outputting theAC after receiving the battery fault instruction.
 15. The electricvehicle according to claim 9, wherein the controller is furtherconfigured to stop outputting the AC after receiving a dischargingfinish instruction from the instrument.
 16. The electric vehicleaccording to claim 9, wherein the controller is further configured todetect a current discharging current in real-time.
 17. A dischargingapparatus for an electric vehicle, comprising: an AC charging interface;a charging connection device, having a first terminal connected with theAC charging interface and a second terminal connected with an exteriorequipment, and configured to transmit an AC output from the AC charginginterface to the exterior equipment; an instrument, configured to send adischarging preparation instruction after receiving a trigger signal; acontroller, configured to communicate with the instrument and to detectwhether the charging connection device is connected with the AC charginginterface after receiving the discharging preparation instruction, andif yes, to switch to an external discharging mode; a battery manager,configured to communicate with the controller and to control an externaldischarging circuit in a high-voltage distribution box of the electricvehicle to be connected after the controller switches to the externaldischarging mode; a power battery, connected with the high-voltagedistribution box and configured to provide a DC via the externaldischarging circuit in the high-voltage distribution box; wherein thecontroller is configured to convert the DC provided by the externaldischarging circuit into the AC and to output the AC to the AC charginginterface so as to discharge to the exterior equipment; the controlleris further configured to detect whether the electric vehicle iscurrently in P gear after it is determined that the charging connectiondevice is connected with the AC charging interface, and if yes, thecontroller switches to the external discharging mode; and the instrumentis further configured to, when the electric vehicle is in the P gear,activate a discharging setting interface through a panel of theinstrument, and to send the discharging preparation instruction to thecontroller after power consumption equipment of the external dischargingmode is set to a household appliance, among a plurality of externaldischarging equipment types, via the discharging setting interface. 18.The discharging apparatus for an electric vehicle according to claim 17,wherein the instrument is further configured to display a prompt forconnecting to the discharging equipment of the household appliancethrough a multi-plug socket.
 19. The discharging apparatus for anelectric vehicle according to claim 18, wherein the instrument isfurther configured to display discharging information including aconnecting state, a current electric quality, a discharging current, andthe power consumption equipment.